Cutting torch



Mai'ch 8, 1938. w. J. SHERMAN CUTTING TORCH 2 Sheets-Sheet 1 Original Filed Nov. 30, 1951 ENTOR MIZLM ATTORN Y March 8, 1938. w. .1. SHERMAN CUTTING TORCH Original Filed Nov. 30, 1951 2 SheetsSheet 2 ATTORNEY Patented Mar. 8, 1 938 omreo STATES PATENT OFFICE Q 7 2,110,181

u 1 CUTTING 'QORQH Wi iam J- She ma B ne N.- a sisnqr to Airflte ductio n Company, Incorporated, New York Y a co pora n o N w or Qri inal appli ation Nov r 30, 1931, S rial N 577,990, Divided and this application October 1-7 @1 4 Se ial N 8,595

3 Claims.

1;? hisin ent 0n ela es to c t n t rc e and i a ic larly a vanta e us q ont ol ing the cu tm O y en up ly melt sli n t rches, i 1

Cotti i m hin and e ree allv universal it m ines. o di r y m o a t c r 0 templateetollower for moving the torch along a path similar to a sketch or template The torchi por i e mec an s of th u t n m in s easily movable and care must be exercised to avoid displacing the torch and its guiding tracer or. template-follower if it becomes necessary to handle the torch during the operation of the cutting machine.

In hand ,cutting torches, plungenoperated valves haying elements thrust against their seats bysprings .and moved into open position by various type et trigger or lever mechanisms are known, but such valvewperating devices are not suitable for ,machine torches because the force exerted against the .trigger .or lever is likely to s a t ch and i s .no t .n and epi ing mechanism.

.-Displacement of the torch by the turning on of the cutting oxy fin supply will .cause the out to start in the wrong place, or the movement .may be so great that .the jet strikes cold metal and. will not out. If the torch is displaced when theattendant operatesthe valve so as ,tothrottle the flow of cutting oxygen, .theaccuracy of the reproductionis destroyed and the work may be rendered useless. :Even in closing of the valve to shut ofiithe cutting oxygen, the torch ,must not be displaced if it is still over the yvork because if the force requiredto operate the valve shifts the torch and its supporting means the displacement occurs while the valve is still open and the cut progressing.

The machine cutting torches of the prior art have been equipped with turn-cocks for .con-

trolling the cutting oxygen supply. The tone required-to rotatethe handle ofa turn-cock is a couple, and there should be no resultant or reaction tending to shift the position of the torch I or its supporting means. in practice, however, turn-cockshave not been satisfactory: because of the difficulty in operating'them,their liability to leakage, and the high cost of manufacture and repair. In orderto'insure against leaks, it has proved=necessary to havethe cocks so tightand stiff in action thatit'was-difficult and often impossible-for an operator to avoidexerting an unbalanced force and displacing the torch in 'his effort; to. make thes-turn-cock'. yield. Theskilland labor required :to .grind in :the iturn-cock valves to their seats made the manufacture of the torches costly, and made it necessary for users to return them to the manufacturer for repairs, with the resulting expense and loss of time in the use of the torch.

object of the invention is to provide a machine cutting torch with valve mechanism which is inexpensive to manufacture and repair, and which operates so easily that it can be used without danger of displacing the torch or its supporting and guiding mechanism ,when the valve is ppened or closed during the operation of the machine.

application is a division .of my ,copending application Serial No. 577,990, filed November 30, 1931.

Other objects, features and advantages of the invention will appear or ,be pointed out as the specification proceeds.

In th a qm y d wi s:

Fig. l is aside view of a machine cutting torch embodying the invention. The torch is broken out at an interrnediate region, and the removable tip is ,not shown. ;From the position of the handle of the cutting oxygen control, that valve may be assumed to .be open.

Fig. 2 .is a view that may be said to bear the relation .of ,a bottom plan to Fig l, the rear block and na tier the shell being in section.

Fig. 3 is a section taken an the line 3- 3 of Fig. ,2, the valve being closed,

Fig. ,4 is a section taken on the line l- 4 of FigfiZ, the valve beingopen.

The torch shown in these views as an illustration of the invention has a valve block 2, head 3, conduit tubes 4, 5 and 61extending between the block and head, and a shell ,7 enclosing the tubes a nd forming the body of the torch." To one side of the torch body, a rack 3 maybe applied for adjusting the terch, in fa holder, toward and from the work. It is unnecessary to show the socketin the head which receives the tip, not represented inthe drawings, or the petssages in the head which cdnduct'the gases from the tubes 4 5 and B to the'e'ntrance portsof the tip. Suflice it to say that the tube 4' 'conducts the usual hose lines. From the socket of the Another passage [8 is drilled from the socket of the oxygen connection 9 to a chamber 20, the axis of which is transverse to the length of the torch. The outer end of this chamber is closed by a cap 2| screwed into a socket in one side of the block, the joint being made tight by a gasket 22. A passage 23 of smaller diameter than the chamber 20 and in line with it communicates with another passage 24, which extends forwardly to the cutting oxygen tube 5.

On the shoulder at the junction between the chamber 20 and the passage 23 an annular lip or valve seat 25 is formed.

A cutting oxygen valve 26 is movable in the chamber 20 to and away from the seat, and is normally closed against the seat by a spring 21 interposed between the valve and the back cap 2|. This valve is used to open and close the passageway in'the torch for the cutting oxygen. It is unseated by pressure applied through a plunger or thrust-rod 28, which is slidable in openings inithe body and in a screw plug 29, which are axially alined with the valve. The plug 29 is screwed into a socket in the side of the block opposite from the socket for the cap 2|, and compresses a packing disc 30, the edge of an opening in which clasps the rod 28 to insure a gastight joint.

A thimble 3! is secured to the side of the block 2' over the-removable plug 29, by means of screws 32 which pass through a basal flange 33 of the thimble. The outer end of the rod 28 projects into this thimble, and the thimble serves as a bearing for the stem 34 of a handle 35, which has a wing-piece 36 for manipulation. The outer end of the thrust rod is preferably received in a recess 31 in the inner end of the'handle stem.

The thimble 3| has two steep helical slots 38 cut through its wall, the edges 39 of, these slots constituting cam elements. A transverse pin 40 is fixed in the stem of the handlefso that its projecting ends coact with the cams. When the handle is turned in one direction,' the cam action carries it inward, thrusting the rod 28, which in turn pushes the valve 26 away from its seat, permitting the oxygen to pass. The'inner ends of the cams, are formed to make rest stops 4|. Whenthe ends of the pin M] are on these terminals the spring is powerless to close the valve. The firstrcontrary turn of the handle releases the spring'to close the valve, and in so doing to restore the handle to normal position. The lengths of the cams correspondto about a quarter turn of the handle. This cam mechanism obtains a substantial mechanical advantage for the handle in operating the valve and thereby reduces the effort required to open the valve. The action is exceedingly easy andprompt in both opening and closing, and the operation of the control has no tendency to move the torch. The thimble 3! is preferably of different material from the block 2. Valve blocks arev most commonly constructed from brass, but a steel thimble is more resistant to wear along the cam slots. The portion of the slots which is most liable to wear is the junction of the helical camface with the rest stop.

said conduit to control the passage of oxygen through the conduit, a spring urging the valve element into closed position, manually actuated means for moving the valve element into open position, said means including a rotatable and slidable stem extending outward from the valve block in a direction substantially normal to the long dimension of the torch body, a bearing in which the stem is rotatably supported, a handle at the outer end of the stem extending to 0pposite sides of the axis of the stem so that the stem can be rotated by a couple force applied to the handle, and means for causing the stem to move axially when rotated including a cam surface and a pin, one of which is on the stem and the other of which is on the bearing that supports the stem, all portions of the cam surface beyond its inner end having a pitch so correlated with the spring pressure that the spring snaps the valve element into closed position.

2. A machine cutting torch comprising an elongated torch body, a valve block connected to the rearward end of the torch body and having a conduit therein through which cutting oxygen flows to the torch body, a valve element in said conduit to control the passage of oxygen through the conduit, a spring urging the valve element into closed position, manually actuated means for moving the valve element into open position, said means including a rotatable and slidable stem extending outward from the valve block in a direction substantially normal to the long dimension of the torch body, a bearing in which the stem is rotatably supported, a handle at the outer end of the stem extending to opposite sides of the axis of the stem so that the stem can be rotated by a couple force applied to the handle, and means for causing the stem to move axially when rotated including a cam surface and a pin, one of which is on the stem and the other of which is on the bearing that supports the stem, said cam surface having a rest stop at one end for holding the stem in its displaced position against the pressure of the spring, the cam surface beyond the rest stop having such a pitch in proportion to the spring strength that the spring moves the stem and shifts the valve element into closed position as soon as the pin is moved beyond the rest stopof the cam surface.

3. A machine cutting torch comprising an elongated torch body, a valve block connected to the rearward end of the torch body and having a conduit therein through which cutting oxygen flows to the torch body, a valve element in said conduit to control the passage of oxygen through the conduit, a spring urging the valve element intoclosed position, manually actuated means for moving the valve element into open position, said means including a rotatable and slidable stem extending outward from the valve block in a direction substantially normal to the long dimension of the torch body, a bearing in which the stem is rotatably supported, a handle at the outer end of the stem extending to opposite sides of the throughout the remainder of its length that the handle is rotated and the valve element moved into closed position by the pressure of the spring whenever the handle is rotated to move the pin out of the rest stop.

WILLIAM J. SHERMAN. 

